Nordyne Furnace Manual M1MB

The Nordyne M1MB furnace is a high-efficiency gas furnace designed for residential heating applications. This multi-speed furnace features advanced combustion technology, electronic ignition, and safety controls. The M1MB series includes various models with BTU ratings from 40,000 to 120,000, suitable for different home sizes and climate conditions. Below are key sections covering safety, installation, operation, maintenance, and troubleshooting.

1. Safety Information 2. Installation Requirements 3. Technical Specifications 4. Operating Instructions 5. Control Settings 6. Venting System 7. Gas Connections 8. Electrical Wiring 9. Maintenance Procedures 10. Troubleshooting Guide 11. Warranty Information

Safety Information

Important safety precautions for installation and operation.

Warning Type	Description
Fire/Explosion Hazard	Keep combustible materials away from furnace
Carbon Monoxide	Ensure proper venting; install CO detectors
Electrical Shock	Disconnect power before servicing
Burn Hazard	Surfaces become hot during operation
Gas Leaks	Check all connections with soap solution

WARNING! Installation must be performed by qualified technician only. Improper installation can cause fire, explosion, or carbon monoxide poisoning.

Installation Requirements

Proper installation guidelines and space requirements.

Location: Install in clean, dry area with adequate combustion air.
Clearances: Maintain 1-inch clearance from combustible materials.
Venting: Follow local codes for vent pipe installation.
Gas Supply: Use approved black iron pipe; install shut-off valve.
Electrical: 120V AC power supply with proper grounding.

CAUTION! Never install in sleeping rooms, bathrooms, or garages. Ensure adequate ventilation.

Technical Specifications

Model Series: M1MB 040A - M1MB 120A
Input BTU/H: 40,000 - 120,000
Output BTU/H: 32,000 - 96,000
Efficiency: 80% AFUE
Gas Type: Natural Gas (convertible to LP)
Electrical: 120V, 60Hz, 1.5A
Blower Motor: Multi-speed PSC
Dimensions: Varies by model (check specific model label)
Weight: 85-120 lbs depending on model

Operating Instructions

Normal operation procedures and thermostat settings.

Thermostat Setting: Set to HEAT mode and desired temperature.
System Start: Furnace will ignite after thermostat call for heat.
Normal Operation: Listen for proper ignition sequence.
Shutdown: System cycles off when thermostat satisfied.
Pilot Light: Electronic ignition - no standing pilot.

Note: Allow 5-minute delay between shutdown and restart for safety.

Control Settings

Furnace control board settings and adjustments.

Control	Function	Setting
Gas Valve	Gas pressure regulation	Factory set - do not adjust
Limit Switch	High temperature safety	Auto-reset 200°F
Blower Speed	Airflow adjustment	Tap settings on motor
Ignition Control	Spark ignition timing	Fixed timing sequence
Pressure Switch	Vent safety verification	Proves draft before ignition

Venting System

Proper vent installation and requirements.

Vent Material: Use approved Category I vent pipe.
Vent Size: Match furnace outlet size (check rating plate).
Clearances: Maintain required clearances to combustibles.
Termination: Follow local code for vent termination location.
Slope: Horizontal vents slope upward 1/4" per foot.

WARNING! Improper venting can cause carbon monoxide buildup leading to serious injury or death.

Gas Connections

Gas line installation and pressure testing.

Pipe Size: Minimum 1/2" for natural gas, 3/8" for LP.
Shut-off Valve: Install within 6 feet of furnace.
Drip Leg: Install sediment trap in gas line.
Pressure Test: Test at 14" water column for 10 minutes.
Leak Check: Use soap solution on all connections.

CAUTION! Gas connections must be made by licensed professional only.

Electrical Wiring

Electrical connections and wiring diagrams.

Power Supply: 120V AC, 15A circuit
Grounding: Proper equipment grounding required
Thermostat: 24V control circuit
Blower Motor: Multi-speed with color-coded wires
Safety Circuits: Series-connected limit switches

Note: Refer to wiring diagram on furnace door for specific connections.

Maintenance Procedures

Regular maintenance schedule and procedures.

Monthly: Check air filter; replace if dirty.
Seasonal: Inspect burners and heat exchanger.
Annual: Professional inspection and cleaning.
Blower: Clean blower wheel and housing annually.
Vents: Inspect vent system for obstructions.

Recommended: Schedule professional maintenance before each heating season.

Troubleshooting Guide

Symptom	Possible Cause	Corrective Action
No heat	Thermostat setting, power, gas supply	Check thermostat, circuit breaker, gas valve
Blower runs continuously	Thermostat fan setting, limit switch	Set thermostat to AUTO, check limit switch
Furnace cycles on limit	Dirty filter, restricted airflow	Replace filter, check vents and registers
No ignition	Gas supply, ignition control	Check gas valve, inspect igniter and flame sensor
Unusual noises	Loose parts, airflow issues	Tighten components, check ductwork

Reset Procedure: Turn power off for 30 seconds, then restore.

Warranty Information

Nordyne M1MB furnace warranty coverage.

Heat Exchanger: 20-year limited warranty
Parts: 5-year limited warranty
Labor: 1-year from date of installation
Registration: Required within 60 days of installation
Transferable: Yes, to subsequent homeowner

For warranty service, contact authorized Nordyne dealer with proof of purchase and installation date.